Noncooperative Cellular Wireless with Unlimited Numbers of Base Station Antennas
TL;DR: A cellular base station serves a multiplicity of single-antenna terminals over the same time-frequency interval and a complete multi-cellular analysis yields a number of mathematically exact conclusions and points to a desirable direction towards which cellular wireless could evolve.
Abstract: A cellular base station serves a multiplicity of single-antenna terminals over the same time-frequency interval. Time-division duplex operation combined with reverse-link pilots enables the base station to estimate the reciprocal forward- and reverse-link channels. The conjugate-transpose of the channel estimates are used as a linear precoder and combiner respectively on the forward and reverse links. Propagation, unknown to both terminals and base station, comprises fast fading, log-normal shadow fading, and geometric attenuation. In the limit of an infinite number of antennas a complete multi-cellular analysis, which accounts for inter-cellular interference and the overhead and errors associated with channel-state information, yields a number of mathematically exact conclusions and points to a desirable direction towards which cellular wireless could evolve. In particular the effects of uncorrelated noise and fast fading vanish, throughput and the number of terminals are independent of the size of the cells, spectral efficiency is independent of bandwidth, and the required transmitted energy per bit vanishes. The only remaining impairment is inter-cellular interference caused by re-use of the pilot sequences in other cells (pilot contamination) which does not vanish with unlimited number of antennas.
Citations
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TL;DR: The purpose of this paper is to investigate the state of the art in channel models of massive MIMO with different antenna array configurations, which can be used for both theoretical analysis and practical evaluation.
Abstract: The exponential traffic growth of wireless communication
networks gives rise to both the insufficient network
capacity and excessive carbon emissions. Massive multiple-input multiple-output (MIMO) can improve the spectrum efficiency
(SE) together with the energy efficiency (EE) and has been
regarded as a promising technique for the next generation
wireless communication networks. Channel model reflects the
propagation characteristics of signals in radio environments and
is very essential for evaluating the performances of wireless communication
systems. The purpose of this paper is to investigate
the state of the art in channel models of massive MIMO. First,
the antenna array configurations are presented and classified,
which directly affect the channel models and system performance.
Then, measurement results are given in order to reflect the
main properties of massive MIMO channels. Based on these
properties, the channel models of massive MIMO are studied
with different antenna array configurations, which can be used
for both theoretical analysis and practical evaluation.
162 citations
Cites background or methods from "Noncooperative Cellular Wireless wi..."
...In order to scale up these benefits, massive MIMO, also named as large-scale antenna system, very large MIMO, or hyper MIMO, has been first put forward in 2010 [8]....
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...Disadvantages Pilot contamination [8] Limited orthogonal pilots as of bounded coherent interval and bandwidth High signal processing complexity [9] Large number of antennas and multiplexing UE...
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...Rayleigh fading channel in the massive MIMO system [8]; namely,...
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TL;DR: This work proposes to design hybrid RF and baseband precoders/combiners for multistream transmission in massive MIMO systems, by directly decomposing the predesigned unconstrained digital precoder/combiner of a large dimension by matrix decomposition.
Abstract: For practical implementation of massive multiple-input multiple-output (MIMO) systems, the hybrid processing (precoding/combining) structure is promising to reduce the high implementation cost and power consumption rendered by large number of radio frequency (RF) chains of the traditional processing structure. The hybrid processing is realized through low-dimensional digital baseband processing combined with analog RF processing enabled by phase shifters. We propose to design hybrid RF and baseband precoders/combiners for multistream transmission in massive MIMO systems, by directly decomposing the predesigned unconstrained digital precoder/combiner of a large dimension. This approach is fundamental and general in the sense that any conventional full RF chain precoding solution of a MIMO system configuration can be converted to a hybrid processing structure by matrix decomposition. The constant amplitude constraint of analog RF processing results in the matrix decomposition problem nonconvex. Based on an alternate optimization technique, the nonconvex matrix decomposition problem can be decoupled into a series of convex subproblems and effectively solved by restricting the phase increment of each entry in the RF precoder/combiner within a small vicinity of its preceding iterate. A singular value decomposition-based technique is proposed to secure an initial point sufficiently close to the global solution of the original nonconvex problem. Through simulation, the convergence of the alternate optimization for such a matrix decomposition-based hybrid processing (MD-HP) scheme is examined, and the performance of the MD-HP scheme is demonstrated to be near-optimal.
161 citations
Cites background from "Noncooperative Cellular Wireless wi..."
...In the limit of an infinite number of antennas, the massive MIMO propagation channel becomes quasi-static, where the effects of uncorrelated noise and fast fading vanish, and such favorable characteristics enables arbitrarily small energy per transmitted bit [2]....
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TL;DR: This paper considers a multipair massive multiple-input-multiple-output two-way relay network, in which multiple pairs of users are served by a relay station with a large number of antennas, which uses maximum ratio combining/maximum ratio transmission and a fixed amplification factor for reception/ transmission.
Abstract: This paper considers a multipair massive multiple-input–multiple-output two-way relay network, in which multiple pairs of users are served by a relay station with a large number of antennas, which uses maximum ratio combining/maximum ratio transmission and a fixed amplification factor for reception/transmission. First, the users' ergodic rates are derived for the case with a finite number of antennas, and then, the rate gain is analyzed when the transmit power of the senders and the relay is sufficiently large. We show that the ergodic rates increase with the number of antennas at the relay, i.e., $N$ , but decrease with the number of user pairs, i.e., $K$ , both logarithmically. The energy efficiency for the network is also investigated when the number of antennas grows to infinity. It is further revealed that the ergodic sum-rate can be maintained while the users' transmit power is scaled down by a factor of $1/N$ or the relay power by a factor of $2K/N$ . This indicates that users obtain an energy efficiency gain of $N$ , but the relay has an energy efficiency gain of $N$ divided by the number of users, i.e., $2K$ .
160 citations
Cites background from "Noncooperative Cellular Wireless wi..."
...Massive MIMO was first proposed in multi-cellular noncooperative networks [1] in which a base station can serve many users via linear processing and approach the performance of using the optimal receiver, when a large antenna array is used at the base station with independent and identically distributed (i....
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21 Dec 2014
TL;DR: A broad review of the research work done in the wireless laboratory of the University of Utah in the past 15 years is presented and a number of appealing features of FBMC waveforms are brought up that make them an ideal choice in the emerging areas of multiuser and massive MIMO networks.
Abstract: Recent discussions on viable technologies for 5G emphasize on the need for waveforms with better spectral containment per subcarrier than the celebrated orthogonal frequency division multiplexing (OFDM). Filter bank multicarrier (FBMC) is an alternative technology that can serve this need. Subcarrier waveforms are built based on a prototype filter that is designed with this emphasis in mind. This paper presents a broad review of the research work done in the wireless laboratory of the University of Utah in the past 15 years. It also relates this research to the works done by other researchers. The theoretical basis based on which FBMC waveforms are constructed is discussed. Also, various methods of designing effective prototype filters are presented. For completeness, polyphase structures that are used for computationally efficient implementation of FBMC systems are introduced and their complexity is contrasted with that of OFDM. The problems of channel equalization as well as synchronization and tracking methods in FBMC systems are given a special consideration and a few outstanding research problems are identified. Moreover, this paper brings up a number of appealing features of FBMC waveforms that make them an ideal choice in the emerging areas of multiuser and massive MIMO networks.
160 citations
Cites background from "Noncooperative Cellular Wireless wi..."
...In the pioneering work of Marzetta [95] it is noted that, in the limit, as the number of BS antennas tends to infinity, the processing gain of the system tends to infinity and, as a result, the effects of both noise and multiuser interference (MUI) are completely removed....
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...Therefore, the network capacity (in theory) can be increased unboundedly by increasing the number of antennas at the BS [95]....
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...Also, different groups have started the development of testbeds to confirm the theoretical observation of [95], in practice, for example....
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...An assumption made by Marzetta [95] and followed by other researchers is that orthogonal frequency division multiplexing (OFDM)may be used to convert the frequency selective channels between each MT and the multiple antennas at the BS to a set of flat fading channels....
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...Motivated by Marzetta’s observations [95] multiple research groups in recent past have studied a variety of implementation issues related to massive MIMO systems, for example, [96–100]....
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Patent•
AT&T1
TL;DR: In this article, a circuit panel network system is provided to interface between a network connection and the electrical circuit, where traditional breakers on the electrical panel that provide overload circuit-protection devices can be replaced with circuit breaker devices that have transceivers and power line communication chipsets in addition to overload circuit protection devices.
Abstract: To provide network connectivity in a building using existing electrical wiring and circuitry, a circuit panel network system is provided to interface between a network connection and the electrical circuit. Traditional breakers on the electrical panel that provide overload circuit-protection devices can be replaced with circuit breaker devices that have transceivers and power line communication chipsets in addition to overload circuit-protection devices. A network interface unit that receives broadband network connectivity from a network demarcation point inside or outside the building can wirelessly transfer data to and from the circuit breaker devices, which then distribute the data over the electrical circuits via the power line communication chipsets on the circuit breaker devices
160 citations
References
More filters
TL;DR: This paper addresses digital communication in a Rayleigh fading environment when the channel characteristic is unknown at the transmitter but is known (tracked) at the receiver with the aim of leveraging the already highly developed 1-D codec technology.
Abstract: This paper addresses digital communication in a Rayleigh fading environment when the channel characteristic is unknown at the transmitter but is known (tracked) at the receiver. Inventing a codec architecture that can realize a significant portion of the great capacity promised by information theory is essential to a standout long-term position in highly competitive arenas like fixed and indoor wireless. Use (n T , n R ) to express the number of antenna elements at the transmitter and receiver. An (n, n) analysis shows that despite the n received waves interfering randomly, capacity grows linearly with n and is enormous. With n = 8 at 1% outage and 21-dB average SNR at each receiving element, 42 b/s/Hz is achieved. The capacity is more than 40 times that of a (1, 1) system at the same total radiated transmitter power and bandwidth. Moreover, in some applications, n could be much larger than 8. In striving for significant fractions of such huge capacities, the question arises: Can one construct an (n, n) system whose capacity scales linearly with n, using as building blocks n separately coded one-dimensional (1-D) subsystems of equal capacity? With the aim of leveraging the already highly developed 1-D codec technology, this paper reports just such an invention. In this new architecture, signals are layered in space and time as suggested by a tight capacity bound.
6,812 citations
"Noncooperative Cellular Wireless wi..." refers background in this paper
...A point-to-point MIMO system [2] requires expensive multiple-antenna terminals....
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TL;DR: Under certain mild conditions, this scheme is found to be throughput-wise asymptotically optimal for both high and low signal-to-noise ratio (SNR), and some numerical results are provided for the ergodic throughput of the simplified zero-forcing scheme in independent Rayleigh fading.
Abstract: A Gaussian broadcast channel (GBC) with r single-antenna receivers and t antennas at the transmitter is considered. Both transmitter and receivers have perfect knowledge of the channel. Despite its apparent simplicity, this model is, in general, a nondegraded broadcast channel (BC), for which the capacity region is not fully known. For the two-user case, we find a special case of Marton's (1979) region that achieves optimal sum-rate (throughput). In brief, the transmitter decomposes the channel into two interference channels, where interference is caused by the other user signal. Users are successively encoded, such that encoding of the second user is based on the noncausal knowledge of the interference caused by the first user. The crosstalk parameters are optimized such that the overall throughput is maximum and, surprisingly, this is shown to be optimal over all possible strategies (not only with respect to Marton's achievable region). For the case of r>2 users, we find a somewhat simpler choice of Marton's region based on ordering and successively encoding the users. For each user i in the given ordering, the interference caused by users j>i is eliminated by zero forcing at the transmitter, while interference caused by users j
2,616 citations
"Noncooperative Cellular Wireless wi..." refers background in this paper
...An alternative to a point-to-point MIMO system is a multiuser MIMO system [3], [4], [5], [6] in which an antenna array simultaneously serves a multiplicity of autonomous terminals....
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Book•
28 Jun 2004TL;DR: A tutorial on random matrices is provided which provides an overview of the theory and brings together in one source the most significant results recently obtained.
Abstract: Random matrix theory has found many applications in physics, statistics and engineering since its inception. Although early developments were motivated by practical experimental problems, random matrices are now used in fields as diverse as Riemann hypothesis, stochastic differential equations, condensed matter physics, statistical physics, chaotic systems, numerical linear algebra, neural networks, multivariate statistics, information theory, signal processing and small-world networks. This article provides a tutorial on random matrices which provides an overview of the theory and brings together in one source the most significant results recently obtained. Furthermore, the application of random matrix theory to the fundamental limits of wireless communication channels is described in depth.
2,308 citations
"Noncooperative Cellular Wireless wi..." refers background in this paper
...It can be shown that the vector φkjΦ ∗ l has exactly the same probability distribution as does any row vector of Φl [15], [16]....
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01 Jan 2004
2,180 citations
TL;DR: It is shown that the dirty paper achievable region achieves the sum-rate capacity of the MIMO BC by establishing that the maximum sum rate of this region equals an upper bound on the sum rate.
Abstract: We consider a multiuser multiple-input multiple- output (MIMO) Gaussian broadcast channel (BC), where the transmitter and receivers have multiple antennas. Since the MIMO BC is in general a nondegraded BC, its capacity region remains an unsolved problem. We establish a duality between what is termed the "dirty paper" achievable region (the Caire-Shamai (see Proc. IEEE Int. Symp. Information Theory, Washington, DC, June 2001, p.322) achievable region) for the MIMO BC and the capacity region of the MIMO multiple-access channel (MAC), which is easy to compute. Using this duality, we greatly reduce the computational complexity required for obtaining the dirty paper achievable region for the MIMO BC. We also show that the dirty paper achievable region achieves the sum-rate capacity of the MIMO BC by establishing that the maximum sum rate of this region equals an upper bound on the sum rate of the MIMO BC.
1,802 citations
"Noncooperative Cellular Wireless wi..." refers background in this paper
...An alternative to a point-to-point MIMO system is a multiuser MIMO system [3], [4], [5], [6] in which an antenna array simultaneously serves a multiplicity of autonomous terminals....
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